[Show abstract][Hide abstract]ABSTRACT: In order to investigate the polarization process in charge exchange reactions, we observed the momentum and angular distribution as well as the nuclear polarization of a proton-rich beta-emitting nucleus, 28P (I
π
= 3 + , T
1/2 = 270 msec), produced through the reaction 28Si+ 9Be at E = 100 MeV/u, by selecting the momentum and the ejection angle. An analysis by using double Gaussian functions resolved the observed momentum distribution into two reaction components, nucleon knockout and pick-up abrasion reactions, as suggested in a previous study. The behavior of the observed angular distribution and nuclear polarization implies the influence of those two components. The momentum dependence of the observed nuclear polarization of 28P could be consistently reproduced by a simple model, in which two reaction components are considered. The present study also shows that the charge exchange reaction at intermediate energy is a useful method to produce polarized beta-emitting nuclei, especially for proton-rich nuclei.

[Show abstract][Hide abstract]ABSTRACT: We report our studies in various fields of Physics through nuclear moments utilizing the β-NMR technique, including material sciences, nuclear structures and fundamental symmetries. Especially, we focus on the recent progress in the studies on the electronic structure in Pt through Knight shifts of various impurities, lattice locations of impurities, electric field gradients, the analysis of nuclear spin in terms of its components, anomaly in the spin expectation value for 9C-9Li mirror pair, the G-parity conservation law, and the Ramsey resonance on UCN for future neutron EDM measurements.

[Show abstract][Hide abstract]ABSTRACT: The degrees of polarization of proton rich nucleus P-28 produced in charge exchange reactions Si-28 + Be-9 -> P-28 + X, and Si-28 + H-1 -> P-28 + X have been observed at 100 A MeV. Utilizing thus obtained polarized nuclei, the magnetic moment of P-28 was remeasured, and vertical bar mu(P-28)vertical bar = 0.3115 (34) mu(N) was obtained. beta-nuclear quadrupole resonance (beta-NQR) of P-28 implanted in alpha-Al2O3 have been observed for the first time, in order to measure the electric quadrupole moment of this nucleus.

[Show abstract][Hide abstract]ABSTRACT: The magnetic moment of 28P(Iπ = 3+, T1/2 = 270.3 ms) has been measured precisely by means of β‐NMR technique. The obtained magnetic moment is ∣μ(28P)∣ = 0.3115 (34) μN. Combined with the magnetic moment of its mirror partner 28Al, the nuclear spin I = 3 is decomposed into its 4 components. The measurement of the Q moment has also been tried. From the preliminary NQR spectrum, it was found that the quadrupole coupling constant eqQ∕h may be slightly larger than the prediction, which may show enhancement of the Q moment.

[Show abstract][Hide abstract]ABSTRACT: We report recent situation of anomaly in spin expectation value found in 9C-9Li mirror pair, recent analysis of the nuclear spin in terms of orbital or intrinsic and proton or neutron, and a result from the study of the G-parity conservation law through β-ray angular correlation in terms of its nuclear orientation.

[Show abstract][Hide abstract]ABSTRACT: The magnetic dipole (μ) and electric quadrupole (Q) moments of short-lived nucleus 22F (Iπ=4+Iπ=4+, T1/2=4.2s) have been measured for the first time by means of the β-NMR technique. A spin polarized 22F beam was produced through the charge exchange reaction of 22Ne and was implanted into single crysltals of NaF and MgF2 for μ and Q measurements, respectively. As a result, |μ(F22)|=(2.69443±0.00039)μN and |Q(F22)|=(3±2)mb was obtained. These values are well reproduced by the shell model calculations.

[Show abstract][Hide abstract]ABSTRACT: The spin lattice-relaxation rates of short-lived unstable nuclei (25)Al and (28)p if, Pt has been measured by means of the beta-NMR technique, in order to study the electronic structure of dilute impurities in Pt. From the obtained spin-lattice relaxation rates, Knight shifts K(c) were estimated to be K(c)[Al in Pt] = (0.45 +/- 0.09)x10(-3) and K(c)[P in Pt] = (4 +/- 2 4) x 10(-3) using the Korringa relation. These values were evaluated by comparing to the first principle Calculations.

[Show abstract][Hide abstract]ABSTRACT: Nuclear structure of proton-rich unstable nucleus 28P has been studied by measuring its g-factor for the first time. The g-factor of 28P (Iπ = 3+, T1/2 = 270.3 ms) was measured by means of β-NMR technique combined with the new polarization technique for charge exchange reaction product in the intermediate energy heavy ion collisions. The obtained g-factor of g = 0.1028(27) is very much quenched from the Schmidt value, but is well reproduced by the shell model (+0.102). In connection with the magnetic moment of the mirror partner and the β-ray transition probability, the orbital angular momenta and intrinsic spins of protons and neutrons have been determined as 〈lp〉 = 0.43(29), 〈ln〉 = 1.85(29), 〈Sp) = 0.28(4), and 〈Sn〉 = 0.44(4).

[Show abstract][Hide abstract]ABSTRACT: An ion-beam is one of the powerful tools applied in nanotechnology and nanoscience. It is expected that the application of highly-charged ion (HCI) beams, which have a higher reactivity in materials, would yield further developments in these fields. For effective applications of HCI beams, it is important to investigate any modifications of irradiated materials from a microscopic point of view. For this purpose, an irradiation-induced defect in a single crystal was analyzed by means of Rutherford backscattering-channeling (RBS) technique. In order to induce defects, Ar6+ and Ar9+ beams with an energy of 100keV were irradiated onto a single crystal of Si. By means of a simple analysis, the depth distribution of disordered Si atoms induced by the irradiation was extracted from the observed RBS-C spectra. The present result implies that the productivity of defects in a Si crystal is enhanced for Ar9+ ions compared with Ar6+ ions in a limited region of the surface.

[Show abstract][Hide abstract]ABSTRACT: We are currently researching a next-generation broadcasting system named "Super Hi-Vision", which provides images with much higher resolution and quality than a high definition television, and are developing displays for this system. We have developed a projector which can display the high-resolution images of Super Hi-Vision (7680×4320 pixels) and has a high dynamic range of 1.1 million to 1. This projector features a serial combination of two modulation blocks: the first block for chrominance modulation and the second block for luminance modulation. While a conventional projector has one modulation block that contains three devices to modulate red, green, and blue light, our projector has another modulation block that contains a device for luminance to further modulate the combined RGB modulated light. This configuration enables the projector to output high-resolution color images by combining three low-resolution devices for chrominance modulation and one high-resolution device for luminance modulation. As a high-resolution device, we have newly devel-oped a 1.75-inch liquid crystal on silicon device with 8192×4320 pixels. In addition, the dynamic range is dramatically improved because this dual modulation scheme minimizes the black levels in projected images. We demonstrated that our projector displays Super Hi-Vision color images and that it has an extremely high dynamic range of 1.1 million to 1 and a fine 10-bit tone reproduction.

[Show abstract][Hide abstract]ABSTRACT: In various fields of nanotechnology, the importance of nanoscale three-dimensional (3D) structures is increasing. In order to develop an efficient process to fabricate nanoscale 3D structures, we have applied highly charged ion (HCI) beams to the ion-beam lithography (IBL) technique. Ar-ion beams with various charge states (1+ to 9+) were applied to fabricate spin on glass (SOG) and Si by means of the IBL technique. The Ar ions were prepared by a facility built at Kochi University of Technology, which includes an electron cyclotron resonance ion source (NANOGAN, 10 GHz). IBL fabrication was performed as a function of not only the charge state but also the energy and the dose of Ar ions. The present results show that the application of an Ar(9+) beam reduces the etching time for SOG and enhances the etching depth compared with those observed with Ar ions in lower charged states. Considering the high-energy deposition of HCI at a surface, the former phenomena can be understood consistently. Also, the latter phenomena can be understood based on anomalously deep structural changes, which are remarkable for glasses. Furthermore, it has also been shown that the etching depth can be easily controlled with the kinetic energy of the Ar ions. These results show the possibilities of the IBL technique with HCI beams in the field of nanoscale 3D fabrication.

[Show abstract][Hide abstract]ABSTRACT: The ion beam lithography (IBL) method is one of the promising techniques that can fabricate 3D nano-structures. In order to develop IBL further, highly charged ion (HCI) beams have been applied to IBL method in our research group. Considering a high reactivity of HCI beams in an irradiated material, it is expected that HCI beams enhance a productivity of damage in irradiated materials compared with singly charged ion beams. This effect will be observed as a change in etching speed of IBL process. In the present study, the HCI effect on IBL was investigated by irradiating Ar9+ and Ar1+ with the fluence of 6.3×1012 to 4.7×1014ptcl./cm2, which is lower than that in our previous study (6.3×1014 to 3.1×1015ptcl./cm2). The Ar9+ and Ar1+ ion beams with E=90keV, which were prepared by an irradiation facility of HCI beams at Kochi University of Technology, were irradiated onto spin-on-glass (SOG) through a stencil mask. In order to investigate an etching process by using BHF solution, the fabrication depth of SOG surface was measured as a function of an etching time. The depth measurements show that an irradiation of HCI beams enhances an etching speed and the fabrication depth. For example, the fabrication depth with Ar9+ beams, which is at least 100nm deeper than that with Ar1+ beams, was achieved. The present result shows a priority of HCI beams to fabricate deeper 3D-structures and gives information required to optimize the fabrication process with keeping a good precision.

[Show abstract][Hide abstract]ABSTRACT: The spin-lattice relaxation times T
1 for short-lived β emitters 25Al(I=5/2, T
1/2=7.2 s) and 28P(I=3, T
1/2=270 ms) in Pt were measured by means of the β-NMR technique. As a result, T
1[25Al in Pt]=(1.1−0.3+0.7) s and T
1[28P in Pt were obtained at temperatures of 17 and 20 K, respectively. The Knight shifts were estimated from the Korringa relation,
which were evaluated by comparing to the first principle calculations.
KeywordsSpin-lattice relaxation-β-NMR-Impurity

[Show abstract][Hide abstract]ABSTRACT: The electric quadrupole (Q) moment of short-lived nucleus 25Al (I
π
=5/2+, T
1/2=7.18 s) has been measured for the first time, by means of the β-NQR technique. The spin polarization of 25Al was produced in heavy ion collisions and was kept in a α-Al2O3 single crystal for as long as 2 s and the quadrupole coupling frequency was obtained as |eqQ/h(25Al in Al2O3)|=(4.05±0.30) MHz. From the result, the Q moment was determined as |Q(25Al)|=(240±20) mb. The present Q moment is larger by 30% than the shell model value of 184 mb, calculated by OXBASH code, which may show additional deformation
of the nucleus.
KeywordsNuclear moment-β-NMR-
25Al-Al2O3
-Relaxation time

[Show abstract][Hide abstract]ABSTRACT: The electric quadrupole (Q) moment of short-lived nucleus (25)Al (I(pi) = 5/2(+), T(1/2) = 7.18 s) has been measured for the first time, by means of the beta-NQR technique. The spin polarization of (25)Al was produced in heavy ion collisions and was kept in a alpha-Al(2)O(3) single crystal for as long as 2 s and the quadrupole coupling frequency was obtained as vertical bar eqQ/h((25)Al in Al(2)O(3))vertical bar = (4.05 +/- 0.30) MHz. From the result, the Q moment was determined as vertical bar Q((25)Al)vertical bar = (240 +/- 20) mb. The present

[Show abstract][Hide abstract]ABSTRACT: The longitudinal and transverse momentum (PL and PYenT) distributions of projectile-like fragments, which were produced with an Ar beam and various targets (C, Al, Nb, Tb, Au),
were measured at E=290A MeV. No significant target effects are found in P L distribution. The width of PT distribution increases with target mass. It is plausible that this result is explained by the deflection of orbit arising
from Coulomb repulsion. The nuclear structural effects are observed in isotopic and isotonic distributions of production cross-sections
of fragments, which are derived from observed momentum distributions.

[Show abstract][Hide abstract]ABSTRACT: The magnetic moment of 28P (I
π
= 3 + , T1/2 = 270.3ms) in the ground state has been measured by the
\upbeta \upbeta -nuclear magnetic resonance method for the first time. The measured magnetic moment of
|\upmu (28\vert \upmu (^{28}P)∣ = 0.309(9)
\upmu N\upmu _{{\rm N}} is well reproduced by the shell model value of +0.306
\upmu N \upmu _{{\rm N} }. The shell model calculation also yields a proton density distribution with a long tail. The present results provide a strong
confirmation of the configuration of the 2s
1/2 proton which should lead to the proton halo.

[Show abstract][Hide abstract]ABSTRACT: The spin-lattice relaxation times T(1) for short-lived beta emitters (25)Al(I = 5/2, T(1/ 2) = 7.2 s) and (28)P(I = 3, T(1/2) = 270 ms) in Pt were measured by means of the beta-NMR technique. As a result, T(1)[(25)Al in Pt] = (1.1(- 0.3)(+0.7)) s and T(1)[(28)P in Pt] > 0.5 s were obtained at temperatures of 17 and 20 K, respectively. The Knight shifts were estimated from the Korringa relation, which were evaluated by comparing to the first principle calculations.